diff --git a/pySim/esim/saip/param_source.py b/pySim/esim/saip/param_source.py
index 79424fd1..9c88537c 100644
--- a/pySim/esim/saip/param_source.py
+++ b/pySim/esim/saip/param_source.py
@@ -124,7 +124,7 @@ class DecimalRangeSource(InputExpandingParamSource):
         return "%0*d" % (self.num_digits, val)  # pylint: disable=consider-using-f-string
 
 class RandomSourceMixin:
-    random_impl = random # TODO secure random source?
+    random_impl = random.SystemRandom()
 
 class RandomDigitSource(DecimalRangeSource, RandomSourceMixin):
     """return a different sequence of random decimal digits each"""